The proliferation of personal computing devices, computing appliances, automobile computers and the like has increased the number of computer platforms that are available to consumers. The different computer platforms typically have different hardware specifications, such as the size of a display included in the platforms. The increase in types of computer platforms has presented a problem to software application developers who develop applications for the different platforms.
For example, the use of automobile computers that provide a graphical user interface (GUI) to a user are becoming common. But automobile manufacturers typically desire to have a unique look to their automobiles, so a standard look and feel to a GUI is not desirable in this instance. As a result, a software application written for one make of automobile will not provide acceptable results on another make of automobile.
Ideally, an application developer could develop one software application that could run on multiple different platforms. However, if the different platforms include different hardware, modifications may have to be made to an application for each platform. For example, suppose a developer writes a software application to run on a platform having a display resolution of 640 pixels×300 pixels. If the application is run on a platform that has a 320×240 display resolution, then visual components written for the higher resolution display will appear cropped on the lower resolution display. Furthermore, displaying a bitmap written for a display of one size on a display of another size produces artifacts in the bitmap display, which renders doing so unacceptable.
FIGS. 1a and 1b exemplify the problem discussed above. FIG. 1a is a diagram of a first display 100 of a first size and FIG. 1b is a diagram of a second display 120 of a second size. The first display 100 includes a title bar 102, a client area 104 and a system tray 106. The second display 120 includes a title bar 122, a client area 124 and a system tray 106. In such a configuration, a graphical user interface is limited to the client area 104, 124 of each display 100, 120.
For purposes of the present discussion, the first display 100 is assumed to have a display aspect ratio of 320 pixels by 240 pixels (horizontal×vertical). The second display 120 is assumed to have a display aspect ratio of 640×300 pixels. Accordingly, the second display 120 has a greater resolution than the first display 100. Also, when a GUI displayed according to pixels on the first display 100 is displayed according to pixels on the second display 120, the GUI will be distorted and will have an undesirable appearance due to disproportional shrinking of the GUI.
This is because display objects are programmed for display on the first display 100 according to pixel size, or some other fixed measurement unit. A rectangular display object 150 is shown, for example, that is defined to be 100 pixels horizontally and 25 pixels vertically. The display object 150, therefore, measures 100×25 on both the first display 100 and the second display. While the rectangle 150 that results on the first display 100 has a length of about one-third of the first display 100, the rectangle 150 has a length of less than one-sixth of the display when displayed on the second display 120. Furthermore, the height of the rectangle 150 on the first display 100 would be about one-tenth of the first display 100, while the height of the rectangle 150 would be about one-twelfth of the display when rendered on the second display 120. Clearly, the same rectangle object 150 appears disproportionate to the client area 124 when rendered on the second display 120.
If a developer were provided a way in which to write an application that could scale its GUI to fit proportionally on different sizes of displays, then the developer would be able to write one application that would operate on a number of different platforms.